Amorphous magnetic material and magnetic core using the same

• US 6,004,661 A
• Filed: 06/24/1998
• Issued: 12/21/1999
• Est. Priority Date: 06/24/1997
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Sakai, Kazumi, Moriya, Yasuaki, Kusaka, Takao
• Primary Examiner(s): MULVANEY, ELIZABETH EVANS
• Application Number:
  US09/103,391
• Time in Patent Office: 545 Days
• Field of Search: 428/216, 428/606, 428/692, 428/694 T, 428/694 TR, 420/435, 420/440, 148/403, 148/408, 148/425
• US Class Current: 428/216
• CPC Class Codes: H01F 1/15308 based on Fe/Ni H01F1/15325 takes precedence
• CPC Class Codes: Y10T 428/115 Magnetic layer composition
• CPC Class Codes: Y10T 428/12431 Foil or filament smaller than 6 mils
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick

Abstract

An amorphous magnetic material possesses a composition essentially expressed by (Fe_1-a-b N_a M_b)_100-x-y Si_x B_y (M denotes at least one kind of element selected from Mn, Cr, Co, Nb, V, Mo, Ta, W and Zr, 0.395≦a≦0.7, 0≦b≦0.21, 1-a-b<a, 6≦x≦18 at %, 10≦y≦18 at %, respectively). An amorphous magnetic material which has such a Ni rich Fe-Ni base possesses a Curie temperature T_c of 473 to 573K, the maximum magnetic flux density B_m of 0.5 to 0.9T. A ratio of residual magnetic flux density B_r and the maximum magnetic flux density B_m can be controlled according to a required characteristics, and, in the case of being used in a saturable core, is set at 0.60 or more. With an amorphous magnetic material of an inexpensive Fe-Ni base, magnetic characteristics applicable in a high frequency region, thermal stability, surface smoothness can be realized.

Claims

1. An amorphous magnetic material essentially consisting of a composition expressed by general formula:

space="preserve" listing-type="equation">(Fe.sub.1-a-b Ni.sub.a M.sub.b).sub.100-x-y Si.sub.x B.sub.y

(in the formula, M denotes at least one kind of element selected from Mn, Cr, Co, Nb, V, Mo, Ta, W and Zr, a, b, x and y are values satisfying 0.395≦

a≦

0.7, 0≦

b≦

0.21, 1-a-b<

a, 6≦

x≦

18 at %, 10≦

y≦

18 at %, respectively).

2. The amorphous magnetic material as set forth in claim 1:

wherein, the M element includes 2 or more kinds of elements selected from Mn, Cr and Co.

3. The amorphous magnetic material as set forth in claim 1:

wherein, the M element includes Mn, Cr and Co.

4. The amorphous magnetic material as set forth in claim 1:

wherein, a content of the M element b satisfies 0.001≦

b≦

0.1.

5. The amorphous magnetic material as set forth in claim 1:

wherein, the content of the Si x and the content of the B y satisfy 15≦

x+y≦

30 at %.

6. The amorphous magnetic material as set forth in claim 1:

wherein, the content of the Si x and the content of the B y satisfy a relation of x<

y.

7. The amorphous magnetic material as set forth in claim 1:

wherein, Curie temperature T_c is 473K or more and 573K or less.

8. The amorphous magnetic material as set forth in claim 1:

wherein, the maximum magnetic flux density B_m is 0.5T or more and 0.9T or less.

9. The amorphous magnetic material as set forth in claim 1:

wherein, a ratio B_r /B_m of a residual magnetic flux density B_r and the maximum magnetic flux density B_m is 0.60 or more.

10. The amorphous magnetic material as set forth in claim 9:

wherein, the ratio B_r /B_m is 0.80 or more.

11. The amorphous magnetic material as set forth in claim 1:

wherein, a ratio B_r /B_m of a residual magnetic flux density B_r and the maximum magnetic flux density B_m is 0.50 or less.

12. The amorphous magnetic material as set forth in claim 1:

wherein, a melting point of the amorphous magnetic material is 1273K or less.

13. The amorphous magnetic material as set forth in claim 1:

wherein, the amorphous magnetic material has a thin film ribbon shape.

14. The amorphous magnetic material as set forth in claim 13:

wherein, an amorphous magnetic material having the thin film ribbon shape has a surface roughness K_s satisfying 1≦

K_s ≦

1.5, wherein the surface roughness is expressed by a value obtained by dividing a sheet thickness measured with a micrometer with 2 flat probe heads by a sheet thickness calculated from its weight.

15. The amorphous magnetic material as set forth in claim 13:

wherein, an amorphous magnetic material having the thin film ribbon shape has an average sheet thickness of 30 μ

m or less.

16. A magnetic core comprising a coiled body or a laminate of an amorphous magnetic material having the thin film ribbon shape as set forth in claim 13.

17. The magnetic core as set forth in claim 16:

wherein, the amorphous magnetic material contains as the M element 2 kinds or more of elements selected from Co, Cr and Mn.

18. The magnetic core as set forth in claim 16:

wherein, the amorphous magnetic material possesses a Curie temperature T_c of 473K or more and 573K or less, the maximum magnetic flux density B_m of 0.5T or more and 0.9T or less, a ratio B_r /B_m of a residual magnetic flux density B_r and the maximum magnetic flux density B_m of 0.60 or more.

19. The magnetic core as set forth in claim 16:

wherein, the amorphous magnetic material possesses a Curie temperature T_c of 473K or more and 573K or less, a ratio B_r /B_m of a residual magnetic flux density B_r and the maximum magnetic flux density B_m of 0.50 or less.

20. A saturable core comprising a coiled body or a laminate of the amorphous magnetic material possessing the thin film ribbon shape as set forth in claim 13:

wherein, the amorphous magnetic material possesses a Curie temperature T_c of 473K or more and 573K or less, the maximum magnetic flux density B_m of 0.5T or more and 0.9T or less, a ratio B_r /B_m of a residual magnetic flux density B_r and the maximum magnetic flux density B_m of 0.60 or more.